Method and process for extracting shale oil and gas by fracturing and chemical retorting in oil shale in-situ vertical well

ABSTRACT

The present invention provides a method and a process for extracting shale oil and gas by fracturing and chemical retorting oil shale in in-situ vertical well. A vertical well ( 1 ) is drilled towards an underground oil shale stratum ( 6 ) and a highly pressurized medium is injected into the oil shale stratum. Cracks of 1 to 3 mm are fractured out in the oil shale stratum with the well serving as a center and are filed with gap fillers, so that oil gas passages ( 8 ) are established. Then, a heating apparatus is added into the oil shale stratum to heat the oil shale stratum to 550° C., the oil shale is initially retorted, the shale oil and gas are extracted, and the shale oil and gas are led out of the ground via the oil and gas channel. After that, an oxidizer is introduced for oxidization reaction with a sphaltenes and fixed carbon contained in the oil shale after being retorted, where the heat generated is used as a heat source for subsequent retorting, thus achieving underground in-situ shale oil extraction. This solves the problem that existing ground-level retorting has in terms of large recovery costs, difficult treatment of tailings, a variety of environmental issues, and large land-use footprint.

BACKGROUND

1. Technical Field

The present invention discloses a method and a process for extractingshale oil and gas by fracturing and chemical retorting oil shale inin-situ vertical well, in which shale oil is extracted in in-situunderground oil shale and is served as unconventional oil and gas energyfor making up shortage of petroleum resources, and which belong to atechnical field of retorting of petroleum.

2. Description of the Related Art

At present, shale oil (artificial petroleum), which is used tosubstitute for naturally occurring petroleum, may be refined from shaleoil by virtue of retorting technology, and is also used for electricitygeneration by utilizing combustion thereof. Under the current situationthat price of the oil keeps high, shale oil refining has good economicbenefits and is a most realistic available measure to make up shortageof naturally occurring petroleum. Electricity generation by oil shalehas good economic, environmental and social benefits to these provincesand districts which encounter shortage of coals. However, production anddevelopment of shale oil always adopts conventional method ofunderground exploitation and on-ground retorting, which encounters lotsof shortcomings

-   -   1). The on-ground retorting has large excavation cost.    -   2). The on-ground retorting needs large land-use footprint.    -   3). The on-ground retorting leads to a great deal of landslide        in exploration area.    -   4). The tailings resulted from the on-ground retorting are        difficult to be treated, and its bulk accumulation causes        secondary pollution.    -   5). The tailings resulted from the on-ground retorting carry        away lots of heat so that heat from the tailings is unavailable,        which results in energy waste.    -   6). Waste gas and sewage obtained from the on-ground retorting        causes excessive pollution of the environment.

SUMMARY

The present invention discloses a method and a process for extractingshale oil and gas by fracturing and chemical retorting oil shale inin-situ vertical well, which fundamentally solve the above mentionedshortcomings and problems caused by underground exploitation andon-ground retorting.

The following is a technical solution of a method for extracting shaleoil and gas by fracturing and chemical retorting oil shale in in-situvertical well disclosed in the present invention.

The method comprises:

-   -   drilling, depending on the situation of an oil shale stratum, a        fractured burning well and several export production wells from        the ground to the underground oil shale stratum, wherein the        export production wells are distributed in a honeycombed manner        around the fractured burning well as a center; establishing a        fracturing chamber within the fractured burning well, to        pressurizedly fracture out the oil shale stratum; injecting a        highly pressurized medium for the oil shale stratum (air, water        and quartz sand) into the fractured burning well, and fracturing        out several cracks of 1 to 3 mm in the oil shale stratum, the        cracks being filled with gap fillers (quartz sand), so as to        establish oil gas passages; establishing a burning chamber        within the fractured burning well, injecting a combustible gas        and a combustion-supporting gas into the burning chamber, and,        igniting the combustible gas so that the combustible gas is        burning at a bottom of the burning chamber (to ignite        combustible matter in the oil shale), to heat the oil shale        stratum up to 550-600° C., to achieve heating and retorting of        the oil shale so that the shale oil and gas are driven and        extracted; exporting the shale oil and gas to the ground through        the oil gas passage and the export production wells;        introducing, in the oil shale stratum, an oxidant through the        vertical well, to oxidize a sphaltenes and fixed carbon remained        in the oil shale after being retorted, where the heat generated        is used as a heat source for subsequent retorting, thereby        achieving extraction of the shale oil and gas by underground        in-situ continuous retorting of the oil shale; separating the        exported shale oil and gas by a ground gas-liquid separator, and        delivering the separated shale oil to a product tank for storage        and sale; and, delivering combustible gas to a gas power package        for power generation.

A process for implementing the mentioned method of extracting shale oiland gas by fracturing and chemical retorting oil shale in in-situvertical well according to the present invention is disclosed. Theprocess comprising the following steps of:

-   -   1). depending on distribution and strike of an oil shale        stratum, selecting specific locations of a fractured burning        well and export production wells, drilling a fractured burning        well and several export production wells from the ground to the        underground oil shale stratum, wherein a drilling depth of the        fractured burning well should not penetrate through the oil        shale stratum, the export production wells should penetrate        through the oil shale stratum, and, the export production wells        are distributed in a honeycombed manner around the fractured        burning well as a center;    -   2). establishing a fracturing chamber within the fractured        burning well, taking out a well casing, injecting a highly        pressurized medium in to the oil shale stratum through the        fractured burning well, pressurizedly fracturing out several        cracks of 1 to 3 mm in the oil shale stratum, and filling the        cracks with gap fillers (quartz sand), so as to establish oil        gas passages; wherein the step 2) further comprises:        -   i). drifting and flushing the well;        -   ii). running a hydraulic casing nozzle into a wellbore;        -   iii). closing the casing and shale wall gaps to form a            closed fracturing space;        -   iv). implementing a hydraulic jet perforation, by the            hydraulic casing nozzle, on the oil shale stratum, wherein a            mortar containing base fluid (water) and sand-laden fluid at            20-35% is pumped at a cutting stage, and, when the            sand-laden fluid is distanced from the nozzle at about 25            meters, pump speed is sharply increased to ensure that a            sufficient pressure different (55-80 MPa) which is required            to implement the hydraulic jet perforation is obtained;        -   v). replacing fracture rocks from the perforation, after 2-3            minutes of operation of the hydraulic jet perforation;        -   vi). pumping crosslinked carbamidine gel and sand (at a rate            of 20-30: 40-60), to enhance an expansion strength;        -   vii). discharging fluid after fracturing, and flushing the            sand to support the cracks;        -   viii). injecting a fluid temporary plugging agent into the            wellbore;        -   vi). lifting up a drilling tool to a designed position, to            fracture a next stratum, and repeating the steps iii). to            vi).;    -   3). establishing a burning chamber within the fractured burning        well; wherein the step 3) further comprises:        -   i). flushing the well, to bring the sand-contained water            within the fractured burning well onto the ground;        -   ii). equipping a sealing casing onto a head of the fractured            burning well and running the sealing casing till 0.5 meter            under the oil shale stratum, and, closing the casing and the            shale wall gaps by means of an expansion agent;        -   iii). Equipping combustible gas and air introducing pipes            and an electronic ignition system within the fractured            burning well, and, closing the head, to form a burning            chamber in a segment of the oil shale stratum;        -   iv). delivering LPG and air into the burning chamber via a            combustible gas delivery pipe, and, igniting the combustible            gas by the electronic ignition system;        -   v). heating the oil shale stratum to 550-600° C. after            igniting the oil shale, stopping supply of the combustible            gas when it is measured that temperature of the gas from the            production well reaches 200° C. and, driving and extracting            some of the shale oil and gas to a ground gas-liquid            separator via oil gas passages and the export production            wells;    -   4). continuing to inject highly pressurized air into the well,        to oxidize a sphaltenes and fixed carbon remained in the oil        shale after being retorted, under high temperature, so as to        generate fresh combustible gas while driving and extracting the        shale oil and gas to the ground via the oil gas passages and the        export production well;    -   5). separating the exported shale oil and gas by the ground        gas-liquid separator, and delivering the separated shale oil to        a product tank for storage; and,    -   6). delivering the separated combustible gas, via the gas-liquid        separator, to a gas power package for power generation.

There are six export production wells distributed in a honeycombedmanner.

The highly pressurized medium is selected from air, water or mortar.

The oxidant is selected from air or oxygen-enriched gas.

The hydraulic casing nozzle mainly comprises an upper centralizer, anejection gun, a check valve, a lower centralizer, a screen pipe and aguide shoe, wherein a surface of the ejection gun is provided with anejection nozzle, the ejection nozzle has one end communicated with thecasing by a nipple and the other end communicated with the screen pipeby the check valve, an outside of the nipple is cased with the uppercentralizer, pipe wall of the screen pipe is uniformly distributed withseveral screen meshes, the lower centralizer is cased over the screenpipe, and, the guide shoe is secured to a top of the screen pipe.

The present invention has the following positive effects.

The shale oil is extracted in in-situ underground oil shale by achemical heat treatment process of fracturing and chemical retorting theshale oil and gas, which avoids bulk exploitation of oil shale mine andaverts environmental pollution brought by on-ground retorting. Secondly,underground continuous retorting is achieved by utilizing a sphaltenesand fixed carbon remained in the oil shale after being retorted,accordingly, the heat is self-sufficient. Thirdly, the chemical heattreatment process is neither a single physical heating process nor anunderground spontaneous combustion process, pores in the rock aregradually increased during the course of reaction, and, it is suitablefor most oil shale strata. The present invention has advantages of smallinvestments, low operating costs, small environmental pollutions, highresource utilization rate, and fast yields of oil and gas, etc..

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a principle diagram of a method for extracting shale oil andgas by fracturing and chemical retorting oil shale in in-situ verticalwell according to the present invention;

FIG. 2 is a structural schematic diagram of distribution of verticalwells according to the present invention; and

FIG. 3 is a structural principle diagram of a hydraulic casing nozzleaccording to the present invention;

in which:

1. fractured burning well, 2. export production well, 3. gas-liquidseparator, 4. product tank, 5. gas power package, 6. oil shale stratum,7. other stratum, 8. oil gas passage, 9. material conveyor, 10.discharge and transport machine, 11. oil pump, 12. crack, 13. fracturingfluid tank, 14. LPG storage tank, 15. oxidant tank, 16. uppercentralizer, 17. ejection gun, 18. ejection nozzle, 19. check valve, 20.lower centralizer, 21. screen pipe, 22. guide shoe, 23. casing, and, 24.nipple.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In order to provide a much clearer understanding of essences andcharacteristics of the present invention, implementation and positiveeffects of the present invention will be described hereinafter in detailin conjunction with these embodiments. It should be understood that thebelow description is not intended to limit the scope of the presentinvention.

Embodiment 1

Fuyu-Changchun Mountain Oil Shale Mine, in which a total reserves is of45.274 billion tons, is taken as an implementation base. The oil shalehas an average grade of 5.53%, an industrially developable resourcestotal amount of 18 billions, an embedded depth of 160-800 meters withtop and bottom strata of mousey shale, and an average thickness of 5meters.

As shown in FIG. 1, depending on distribution and strike of an oil shalestratum, specific locations of a fractured burning well and exportproduction wells are selected, a fractured burning well 1 (a head ofwhich has a diameter of 200 mm) and six export production wells 2 (ahead of each of which has a diameter of 200 mm) are drilled from aunderground rock stratum 7 to a underground oil shale stratum 6 (whichis distanced from the ground at 380 meters). As shown in FIG. 2, the sixexport production wells 2 are distributed in a honeycombed manner aroundthe fractured burning well 1 as a center. The fractured burning well andthe export production wells are drilled from the ground to theunderground oil shale stratum, wherein a drilling depth of the fracturedburning well should not penetrate through the oil shale stratum, theexport production wells should penetrate through the oil shale stratum,and, the export production wells are distributed in a honeycombed manneraround the fractured burning well as a center.

-   -   2). A fracturing chamber is established within the fractured        burning well, a well casing is taken out, a highly pressurized        medium is injected into the oil shale stratum through the        fractured burning well, several cracks of 1 to 3 mm are        pressurizedly fractured out in the oil shale stratum, and the        cracks are filled with gap fillers (quartz sand), so as to        establish oil gas passages. The step 2) further comprises:        -   i). drifting and flushing the well;        -   ii). running a hydraulic casing nozzle into a wellbore;        -   iii). closing the casing and shale wall gaps to allow the            oil shale stratum to form a closed fracturing space;        -   iv). implementing a hydraulic jet perforation, by the            hydraulic casing nozzle, on the oil shale stratum 6, wherein            a mortar containing base fluid (water) and sand-laden fluid            (at 20-35%) is injected from the fracturing fluid tank 13            into the oil shale stratum 6 by a material conveyor 9 (at a            cutting stage), and, when the sand-laden fluid is distanced            from the nozzle at about 25 meters, pump speed is sharply            increased to ensure that a sufficient pressure different            (55-80 MPa) which is required to implement the hydraulic jet            perforation is obtained to fracture the oil shale stratum 6            to generate cracks 12 of 1-3 mm;        -   v). replacing fracture rocks from the perforation, after 2-3            minutes of operation of the hydraulic jet perforation;        -   vi). pumping carbamidine gel base fluid by an annular bore,            in accordance with a design annular bore discharge capacity            or at a maximum pump speed allowed by an maximum pressure of            annular bore, and, pumping crosslinked gel and sand, in            accordance with a design of an oil pipe, (to enhance an            expansion strength);        -   vii). discharging fluid after fracturing, wherein the quartz            sand is remained to support the cracks, forming a plurality            of oil gas passages 8, the plurality of oil gas passages 8            being converged and communicated with the export production            well 2;        -   viii). injecting a fluid temporary plugging agent into the            wellbore;        -   iv). lifting up a drilling tool to a designed position, to            fracture a next stratum, and repeating the steps iii). to            vi).    -   3). A fracturing chamber is established within the fractured        burning well. The step 3) further comprises:        -   a first step of, flushing the well, to bring the            sand-contained water out of the well onto the ground;        -   a second step of, equipping a sealing casing onto a head of            the fractured burning well and running the sealing casing            till 0.5 meter under the oil shale stratum, and, closing the            casing and the shale wall gaps by means of an expansion            agent;        -   a third step of, equipping combustible gas and air            introducing pipes and an electronic ignition system within            the fractured burning well, and, closing the head, to form a            burning chamber in a segment of the oil shale stratum;        -   a fourth step of, delivering LPG and air from a LPG storage            tank 14 and an oxidant tank 15 respectively through the            fractured burning well 1 into the oil shale stratum 6 by a            material conveyor 9, and, igniting the combustible gas by            the electronic ignition system;        -   a sixth step of, heating the oil shale stratum 6 to            550-600° C. after igniting the oil shale, stopping supply of            the combustible gas when it is measured that temperature of            the gas from the production well 2 reaches 200° C. and,            driving and extracting some of the shale oil and gas to a            ground gas-liquid separator 3 via oil gas passages 8 and the            export production wells 2;        -   introducing an oxidant into the oil shale stratum 6 to            oxidize a sphaltenes and fixed carbon remained in the oil            shale after being retorted, where the heat generated is used            as a heat source for subsequent retorting the subsequent oil            shale progressively, wherein the generated shale oil and gas            are passed through;    -   4). continuing to inject highly pressurized air (the air: 1000        m³ per hour) from the oxidant tank 15 into the fractured burning        well 1 by a material conveyor 9, to oxidize asphaltenes and        fixed carbon remained in the oil shale 6 after being retorted,        under high temperature, so as to generate fresh combustible gas        (while driving the shale oil and gas) to the gas-liquid        separator 3 via the oil gas passages 8 and the export production        well 2, so that the underground in-situ extraction of the shale        oil and gas is achieved;    -   5). separating the exported shale oil and gas by the ground        gas-liquid separator 3, and delivering the separated shale oil        to a product tank 4 for storage and sale, by an oil pump; and,    -   6). delivering the separated combustible gas, via the gas-liquid        separator 3, to a gas power package 5 for power generation, by a        discharge and transport machine 10.

Embodiment 2

Qiangguo Oil Shale Mine, in which a total mining area is of 675.5 km²,the total resources is of 6.172 billion tons and the exploitable totalresources is of 4.94 billion tons, is taken as an implementation base.The oil shale has an average grade of 5%, an embedded depth of 160-800meters with top and bottom strata of mousey shale, and an averagethickness of 6 meters.

As shown in FIG. 1, depending on distribution and strike of an oil shalestratum, specific locations of a fractured burning well 1 and exportproduction wells 2 are selected, a fractured burning well 1 (a head ofwhich has a diameter of 200 mm) and six export production wells 2 (ahead of each of which has a diameter of 200 mm) are drilled from aunderground rock stratum 7 to a underground oil shale stratum 6 (whichis distanced from the ground at 380 meters). As shown in FIG. 2, the sixexport production wells 2 are distributed in a honeycombed manner aroundthe fractured burning well 1 as a center. The fractured burning well andthe export production wells are drilled from the ground to theunderground oil shale stratum, wherein a drilling depth of the fracturedburning well should not penetrate through the oil shale stratum, theexport production wells should penetrate through the oil shale stratum,and, the export production wells are distributed in a honeycombed manneraround the fractured burning well as a center.

-   -   2). A fracturing chamber is established within the fractured        burning well, a well casing is taken out, a highly pressurized        medium is injected into the oil shale stratum through the        fractured burning well, several cracks of 1 to 3 mm are        pressurizedly fractured out in the oil shale stratum, and the        cracks are filled with gap fillers (quartz sand), so as to        establish oil gas passages. The step 2) further comprises:        -   i). drifting and flushing the well;        -   ii). running a hydraulic casing nozzle into a wellbore;        -   iii). closing the casing and shale wall gaps to allow the            oil shale stratum to form a closed fracturing space;        -   iv). implementing a hydraulic jet perforation, by the            hydraulic casing nozzle, on the oil shale stratum 6, wherein            a mortar containing base fluid (water) and sand-laden fluid            (at 20-35%) is injected from the fracturing fluid tank 13            into the oil shale stratum 6 by a material conveyor 9 (at a            cutting stage), and, when the sand-laden fluid is distanced            from the nozzle at about 25 meters, pump speed is sharply            increased to ensure that a sufficient pressure different            (55-80 MPa) which is required to implement the hydraulic jet            perforation is obtained to fracture the oil shale stratum 6            to generate cracks 12 of 1-3 mm;        -   v). replacing fracture rocks from the perforation, after 2-3            minutes of operation of the hydraulic jet perforation;        -   vi). pumping carbamidine gel base fluid by an annular bore,            in accordance with a design annular bore discharge capacity            or at a maximum pump speed allowed by an maximum pressure of            annular bore, and, pumping crosslinked gel and sand, in            accordance with a design of an oil pipe, (to enhance an            expansion strength);        -   vii). discharging fluid after fracturing, wherein the quartz            sand is remained to support the cracks, forming a plurality            of oil gas passages 8, the plurality of oil gas passages 8            being converged and communicated with the export production            well 2;        -   viii). injecting a fluid temporary plugging agent into the            wellbore;        -   iv). lifting up a drilling tool to a designed position, to            fracture a next stratum, and repeating the steps iii). to            vi).    -   3). A fracturing chamber is established within the fractured        burning well. The step 3) further comprises:        -   a first step of, flushing the well, to bring the            sand-contained water out of the well onto the ground;        -   a second step of, equipping a sealing casing onto a head of            the fractured burning well and running the sealing casing            till 0.5 meter under the oil shale stratum, and, closing the            casing and the shale wall gaps by means of an expansion            agent;        -   a third step of, equipping combustible gas and air            introducing pipes and an electronic ignition system within            the fractured burning well, and, closing the head, to form a            burning chamber in a segment of the oil shale stratum;        -   a fourth step of, delivering LPG and air from a LPG storage            tank 14 and an oxidant tank 15 through the fractured burning            well 1 into the oil shale stratum 6 by a material conveyor            9, and, igniting the combustible gas by the electronic            ignition system;        -   a sixth step of, heating the oil shale stratum 6 to            550-600° C. after igniting the oil shale, stopping supply of            the combustible gas when it is measured that temperature of            the gas from the production well 2 reaches 200° C. and,            driving and extracting some of the shale oil and gas to a            ground gas-liquid separator 3 via oil gas passages 8 and the            export production wells 2;        -   introducing an oxidant into the oil shale stratum 6 to            oxidize a sphaltenes and fixed carbon remained in the oil            shale after being retorted, where the heat generated is used            as a heat source for subsequent retorting the subsequent oil            shale progressively, wherein the generated shale oil and gas            are passed through;    -   4). continuing to inject highly pressurized air (the air: 1000        m³ per hour) from the oxidant tank 15 into the fractured burning        well 1 by a material conveyor 9, to oxidize a sphaltenes and        fixed carbon remained in the oil shale 6 after being retorted,        under high temperature, so as to generate fresh combustible gas        (while driving the shale oil and gas) to the gas-liquid        separator 3 via the oil gas passages 8 and the export production        well 2, so that the underground in-situ extraction of the shale        oil and gas is achieved;        -   separating the exported shale oil and gas by the ground            gas-liquid separator 3, and delivering the separated shale            oil to a product tank 4 for storage and sale, by an oil            pump; and,        -   delivering the separated combustible gas, via the gas-liquid            separator 3, to a gas power package 5 for power generation,            by a discharge and transport machine 10.

Embodiment 3

Referring to FIG. 3, there discloses a hydraulic casing nozzle involvedin embodiments 1 and 2, it mainly comprises an upper centralizer 16, anejection gun 17, a check valve 19, a lower centralizer 20, a screen pipe22, a guide shoe 23, a casing 23 and a nipple 24, wherein a surface ofthe ejection gun 17 is provided with an ejection nozzle 18, the ejectionnozzle 17 has one end communicated with the casing 23 by a nipple 24 andthe other end communicated with the screen pipe 21 by the check valve19, an outside of the nipple 24 is cased with the upper centralizer 16,pipe wall of the screen pipe 21 is uniformly distributed with severalscreen meshes, the lower centralizer 20 is cased over the screen pipe21, and, the guide shoe 22 is secured to a top of the screen pipe 21.

1. A method for extracting shale oil and gas by fracturing and chemicalretorting oil shale in in-situ vertical well, the method comprising:drilling a fractured burning well and several export production wellsfrom the ground to an the underground oil shale stratum, wherein theexport production wells are distributed in a honeycombed manner aroundthe fractured burning well as a center; establishing a fracturingchamber within the fractured burning well, to pressurizedly fracture outthe oil shale stratum; injecting a highly pressurized medium for the oilshale stratum comprising air, water and a gap filler into the fracturedburning well, and fracturing out several cracks of 1 to 3 mm in the oilshale stratum, the cracks being filled with the gap filler, so as toestablish oil gas passages; establishing a burning chamber within thefractured burning well by injecting a combustible gas and acombustion-supporting gas into the burning chamber, and igniting thecombustible gas so that the combustible gas burns at a bottom of theburning chamber to ignite combustible matter in the oil shale, to heatthe oil shale stratum up to 550-600° C., to achieve heating andretorting of the oil shale so that the shale oil and gas are driven andextracted; exporting the shale oil and gas to the ground through the oilgas passage and the export production wells thereby achieving extractionof the shale oil and gas by underground in-situ continuous retorting ofthe oil shale.
 2. A process for implementing the method of extractingshale oil and gas by fracturing and chemical retorting oil shale inin-situ vertical well according to claim 1, the process comprising thefollowing steps of: 1) selecting specific locations of a fracturedburning well and export production wells and drilling a fracturedburning well and several export production wells from the ground to theunderground oil shale stratum, wherein a drilling depth of the fracturedburning well does not penetrate through the oil shale stratum, whereinthe export production wells penetrate through the oil shale stratum, andwherein the export production wells are distributed in a honeycombedmanner around the fractured burning well as a center; 2) establishing afracturing chamber within the fractured burning well, taking out a wellcasing, injecting a highly pressurized medium in to the oil shalestratum through the fractured burning well, pressurizedly fracturing outseveral cracks of 1 to 3 mm in the oil shale stratum, and filling thecracks with a gap filler, so as to establish oil gas passages; whereinthe step 2) further comprises: i). drifting and flushing the well; ii).running a hydraulic casing nozzle into a wellbore; iii). closing thecasing and shale wall gaps to form a closed fracturing space; iv).implementing a hydraulic jet perforation, by the hydraulic casingnozzle, on the oil shale stratum, wherein a mortar containing base fluid(water) and sand-laden fluid at 20-35% is pumped at a cutting stage,and, when the sand-laden fluid is distanced from the nozzle at about 25meters, pump speed is sharply increased to produce a sufficient pressuredifference to implement hydraulic jet perforation; v). replacingfracture rocks from the perforation, after 2-3 minutes of operation ofthe hydraulic jet perforation; vi). pumping crosslinked carbamidine geland sand (at a rate of 20-30: 40-60), to enhance an expansion strength;vii). discharging fluid after fracturing, and flushing the sand tosupport the cracks; viii). injecting a fluid temporary plugging agentinto the wellbore; iv). lifting up a drilling tool to a designedposition, to fracture a next stratum, and repeating the steps iii). tovi).; 3). establishing a burning chamber within the fractured burningwell; wherein the step 3) further comprises: i). flushing the well, tobring sand-containing water within the fractured burning well onto theground; ii). equipping a sealing casing onto a head of the fracturedburning well and running the sealing casing until 0.5 meter below theoil shale stratum, and, closing the casing and the shale wall gaps bymeans of an expansion agent; iii). introducing combustible gas and airintroducing pipes and an electronic ignition system within the fracturedburning well, and, closing the head, to form a burning chamber in asegment of the oil shale stratum; iv). delivering liquid petroleum gas(LPG) and air into the burning chamber via a combustible gas deliverypipe, and, igniting the combustible gas by the electronic ignitionsystem; and v). heating the oil shale stratum to 550-600° C. afterigniting the oil shale, stopping supply of the combustible gas when itis measured that temperature of the gas from the production well reaches200° C. and, driving and extracting the shale oil and gas to a groundgas-liquid separator via oil gas passages and the export productionwells.
 3. A hydraulic casing nozzle, comprising an upper centralizer, anejection gun, a check valve, a lower centralizer, a screen pipe and aguide shoe, wherein a surface of the ejection gun is provided with anejection nozzle, the ejection nozzle has one end in communication withthe casing by a nipple and the other end in communication with thescreen pipe by the check valve, wherein an outside of the nipple iscased with the upper centralizer, wherein a pipe wall of the screen pipeis uniformly distributed with several screen meshes, wherein the lowercentralizer is cased over the screen pipe, and wherein the guide shoe issecured to a top of the screen pipe.
 4. The method of claim 1, whereinthe gap filler is quartz sand.
 5. The method of claim 1, furthercomprising: introducing in the oil shale stratum an oxidant through thevertical well, to oxidize a sphaltenes and fixed carbon remaining in theoil shale after being retorted.
 6. The method of claim 1, where the heatgenerated is used as a heat source for subsequent retorting.
 7. Themethod of claim 1, further comprising separating the exported shale oiland gas by a ground gas-liquid separator.
 8. The method of claim 7,further comprising delivering the separated shale oil to a product tankfor storage and sale.
 9. The method of claim 1 further comprisingdelivering combustible gas to a gas power package for power generation.10. The process of claim 2, wherein the gap filler is quartz sand. 11.The process of claim 2, further comprising continuing to inject highlypressurized air into the well, to oxidize sphaltenes and fixed carbonremaining in the oil shale after being retorted, under high temperature,so as to generate fresh combustible gas while driving and extracting theshale oil and gas to the ground via the oil gas passages and the exportproduction well.
 12. The process of claim 2, further comprisingseparating the exported shale oil and gas by the ground gas-liquidseparator.
 13. The process of claim 12, further comprising deliveringthe separated shale oil to a product tank for storage.
 14. The processof claim 13, further comprising delivering the separated combustiblegas, via the gas-liquid separator, to a gas power package for powergeneration.